Duplex steam-pump.



N0. 830,723. PATENTED SEPT. 11, 1906.

J. KOFOED.

DUPLEX STEAM PUMP. APPLIOATIOH FILED JAN. 9, 1906.

2 SHEETS-SHEET 1.

UL'Ifne ss e s .1

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water end of said pump being not shown, as

UNITED STATES PATENT OFFICE.

JO HAN'KOFOED. OF GHRISTIANIA, NORWAY.- DUPLEX STEAM-PUMP.-

Application filed January 9, 1906. Serial No. 295,236.

Specification of Letters Patent.

Patented Sept. 11, 1906'.

tains to make and, use the same, referencebeing had to the accompanying drawings, and to figures of reference marked thereon, which form a part of this specification.

My invention relates to duplex steampumps; and it has for its object to provide a l valve mechanism therefor which will materially increase the efficiency of the pump or engine, promote its durability, and secure a considerable saving in the steam used to opcrate the same.

To these ends my invention consists in the valve mechanism constructed and as hereinafter'fully described, and particularly pointed out in the claims. 1 Referrin to the drawings, in which like numerals iiesignate like parts in the several figures, Figure 1 is a cross-section of a directacting duplex steam-pump'embodying my invention, taken at the lines 1 1 of Fig. 2. Fig. 2 is a vertical longitudinal section thereof taken at line 2 2 of Fig. 1 Fig. 3 is a plan view of the valve and. its operating-cams. Fi 4 is a cross-section of the two pistonro s and the valve-rod, an end view of one of the cam members on said valve-stem, and a side view ofthe two arms which actuate said cam members. Figs. 5, 6, and 7 are crosssections of the valve-chest and valve taken at lines 5 5, 6 6, and 7 7 of Fig. 2. Fig. 8 is an end view of the valve-rod, and Figs. 9 and 10 show details of the same.

The numerals 1 and 2 designate the two steam-cylinders, 3 and 4 the two pistonheads, and 5 and 6 the two piston-rods ofa common form of duplex steam-pump, the

its construction and mode of'operation are well known. 7 and 8 are actuating-arms on the piston rods. In lieu of the various forms of slide and other valves heretofore employed for admitting steam to and exhausting it from said cylinders 1 and 2, I have devised a single revoluble valve for performmg such function, together with means for operating valve-rod an transmitting a revolving movement to said valve from the piston-rods 5 and 6, and will now proceed to describe the same.

Between'the steam-cylinders 1 and 2 is located a-valve chamber 13 of cylindrical shape, in which chamber is centrally located the cylindrical valve 16, said valve being capable of a free revolving movement Within the chamber and having the valve-rod 26 projecting therefrom through one of the end walls or heads of the chamber.

9 10 and 11 12, respectively, are the steamports between the two cylinders and the valve-chamber 13 common to both of them.

14 is the live-steam inlet, and 15 the exhaust-opening. In the valve 16 is formed a central passage 17 for the exhaust-steam, while the space outsideof the valve forms the passage for the live steam. The exhaust-;

passage 17 terminates at each end of the valve in two diametrically-opposed ports 18 19' and 20 21 ,respectively, which at certain positions of the valve correspond with the ports of the steam-cylinders. Between said exhaust-ports there are in the valve at each end formed live-steam ports 22 23 and 24 25, respectively, which open in the live-steam space of the valve-chamber, and at given positions of the valve correspond with the ports of the steam-cylinders.

Upon the valve-rod 26 are secured two cam members, each of which consists of a split collar embracing said valve-rod, from the end of which cam members project two oppositely-located fingers 2728 respectively,

'each of'said fingers having one of its side ed es parallel to the axis of said its opposite edge atan angle thereto. The fingers of the two each mem-- bers project toward each other and, 'termi-'- nate at a point substantially midwaybetween said members: As shown in Fig. 3,

,the fingers 27 28 of the one cam member are offset at an angle of ninety degreees with respect to the fingers 29 30 of the other cammember; but in order to enable such relative position to be varied for the purpose of varying the point in the stroke at which the cut-- off will occur I may make said cam members adjustable about the axis of the valve-rod. I prefer, however, tomake use of an adjustment device a's shown in Figs. 2 and 3 and Figs. 8, 9, and 10. In the adjustment device shown means are provided whereby the a cavity 32, taking up a spring 33. Throughthe head are inserted two pins 34, between which is formed a guide for a-coupling member (shown in Figs. 9 and 10) having a part correspondingin shape to the guide-space between .the two pins 34*, said part 35being-of a twisted form. The-head36-of the coupling member has a rectangular shape and fits into a'similarly-shaped notch-37 int-he end of the valve-body. 1n the head 36' is secured a long rod 38, whichabuts against a screw 39, carryingthe hand-wheel" 40; by means of which the screw may be screwed out'. If the screw 39 is turned, it will allowthe rod'38' to move outward, and the spring 33- will press the coupling member- 35 36 outwardly, and onaccount of the twisted form-of the part 35 this: movement will cause a turning movement of the valve relativelyto the valve-rod.

The: operation of the valve 1 is as follows The valvleis caused to rotate in one and the same direction, thereby alternately ad mitt-ingsteam to the .two steam-cylinders. In) the position ofthe-partsshown in Fig. 2 the ste'amis p assin'ginto and out" of the 'cyl inder- 2, as indieated by arrows. The actuating member 8 is then moving-to theleft' and will in-the moment'shownibe 'about to hit the cam 27, whereby steam will besuccessively out off from the cylinderZ andbefore the piston in this cylinder'has cometo it's'ex-treme position the valve will have been turned so muchthatsteamis-admittedinto the cylinder 1 at its left end. The 'piston-of that cylinderwill then-move to the right in Fig. 2 and the actuating member, 7 will, when it has passed half way of thestroke, hit the cam30 and c'ausea-new turning movement of the valve, whereby steam will be admitted 'inthe cylinder 2on1 the left side of the piston, and soon The required degreeof expansion of the steam-may be regulated by means of the hand wheel40;

said stemso asto impart an intermittentirotary movement to the valve-in-one andthe same direction, thereby alternately admitting and exhausting steam to andfrom-the said steam-cylinders respectively.

2. The combination withthe two steamcylinders, pistons, and piston-rods of a direct-acting, duplex steam-pump, of a steamchest having a revoluble valve provided with passages adapted to register with the steam ,inlet and exhaust passages of both of said cylinders, said valve having its axis extended beyond the valve-chamber in a plane parallel with said piston-rods and having said axis provided with a plurality of spirally-disposed surfaces, of an engaging device mounted upon each of said p1ston-rodsfor-engag1ng said spirally-disposed surfaces in both direce tions of -movementof said rods to impart a revolving movement'to saidvalve, substan tially as described.

3. The combination with the steam-cylinders, pistons andpiston-rods ofadirect-acting, duplex steam-pump of asteam-chest containing arevoluble valve having passages for registering with the steam inlet and exhaust passages of'said'cylinders, said valve having its operating-stemproj ectedin a plane parallel with said piston-rods and having mounted uponsaid stem two oppositely-projectingcam members and'two engaging-arms upon said piston-rods'for engaging said'cam members to imp art a revolving movement to the valve, substantially as described;

4. The combination with the steam-cylinders of a duplex steam-pump and their pistons, of a cylindricalvalve-chamber the axis ofwhich is parallel with the .axis of said steam-cylinders and'whichis connecte'd'by a passage at each of'its ends with the corresponding ends ofsaid cylind'ers, a cylindrical valve located within said chamber and having its operating-stem-provided with-two -op positely-inclined surfaces, and contactdevices carrie'dby the steam-pistons which are adapted toalternately engage said inclined surfaces on said stem and thereby impart an intermittent revolving movement" to the valve in one and the same-direction, substantially as described, andmeans-to adjust the stem with-its inclined surfaces-relatively to the valve.

5. The combination with the steam-cylin ders-of a duplex steam-pump and their pistons, ofa cylindrical valve-chamber the axis of which is parallel with the axis of said steam-cylinders and whichis-connected by a passage at each of its'endswiththe corre sponding endsof said cylinders, a cylindrical valve located within said chamber and having its operating-stem provided with two oppositely-inclined surfaces, and contact devices carried by the steam-pistonswhich are adapted to-alternately engage said inclined surfaces on said stem and thereby impartan intermittent revolving movement to the movable coupling member, having a straight I In testimony that I claim the foregoing as part engaging the valve and a twisted part my invention 1 have signed my name in presengagingthe valve-stem, a spring pressing I ence of two subscribing witnesses.

the coupling member outwardly from the a J OHAN KOFOED. 5 valve-stem and a screw-spindle adjusting the Witnesses:

position of the coupling member relatively to HENRY BoRDEwIoH,

the valve and the valve-stem. MICHAEL ALGER. 

